Centrifugal pump

ABSTRACT

Disclosed herein is a centrifugal pump having a sealed circular chamber and an annular raceway in the chamber adjacent the periphery thereof. Roller elements are freely positioned within said raceway and these roller elements are rotated on the raceway by a rotating magnetic field positioned outside the chamber. An inlet near the center of the chamber administers fluid to the pump which centrifugally forces the fluid out an outlet adjacent the periphery of the chamber by the rotation of the roller elements.

United States Patent Rene Fays, deceased late of Maisons-Laffitte, France by Reine Marguerite Fays, Renee Helene Fays, Rolande Jose Fays, heirs, 34 Bis, rue de la Muette, 78 Maisons-Laflitte, France [21] Appl. No. 871,814

[22] Filed Mar. 4, 1969 [45] Patented Sept. 28, 1971 [72] inventor [54] CENTRIFUGAL PUMP 15 Claims, 3 Drawing Figs.

[52] U.S.Cl 417/420 [51] Int. Cl F04d 13/02 [50] Field of Search 103/87, 87 M,87AG,118,1M,43;230/1l7,l5 MC, 1,55; 417/420 [56] References Cited UNITED STATES PATENTS 1,071,847 9/1913 Wilson 103/1 X 1,307,210 6/1919 Newcomb 103/118 2,730,951 1/1956 Dorelian et a1. 103/1 2,847,936 8/1958 Richter 103/1 2,875,695 3/1959 Justice 103/43 FOREIGN PATENTS 1,160,135 12/1963 Germany 230/55 Primary Examiner-Robert M. Walker AltorneySherman and Shalloway ABSTRACT: Disclosed herein is a centrifugal pump having a sealed circular chamber and an annular raceway in the chamber adjacent the periphery thereof. Roller elements are freely positioned within said raceway and these roller elements are rotated on the raceway by a rotating magnetic field positioned outside the chamber. An inlet near the center of the chamber administers fluid to the pump which centrifugally forces the fluid out an outlet adjacent the periphery of the chamber by the rotation ot'the roller elements.

PATENTED SEP28 19m 3 09 0 FIG. 2

INVENI0RS RENE FAYS BY Swim/1% ATTORNEYS CENTRIFUGAL PUMP Centrifugal pumps of the prior art used for lifting or circulating liquids usually comprise a rotor with vanes, rotating in a chamber of circular section. The chamber communicates with the exterior by a conduit that is often tangential through which the fluid passes due to the centrifugal force created by the vanes.

Fluid which is introduced centrally of the chamber is rotated by the vanes of the rotor and is projected centrifugally towards the periphery of the circular chamber where it leaves the chamber through a lateral conduit. The rotor is generally mounted at the end of the shaft and rotates at one or more bearings. The shaft goes usually through the wall or walls of the circular chamber and to prevent the fluid from leaking out of the chamber passed the bearings, some type of sealing structure is provided. This structure operates under severe conditions as it must block passage of fluid adjacent the rotating shaft. The shaft normally rotates at high speeds but sufiicient pressure must be maintained on the seal to avoid leaks. This results generally in local heating and rapid wear. Numerous devices, more or less complicated, have been proposed to ensure the prevention of leaks in centrifugal pumps. in certain cases, where any leaks whatever are to be avoided, for instance where the pump is propelling volatile, or dangerous liquids and must be isolated from workers in the area of the pump at all cost, proposals have been made to enclose in the pumping chamber the bearings of the rotor shaft. in these devices, the rotation of the rotor is caused from the outside of the chamber by some magnetic force. In this form of device, leakage is effectively precluded, but other difficulties arise due to the contact that is inherent between the bearings and the liquid. Wear and corrosion often result from this contact as well as other deliterious reaction between the bearings and the fluid.

The present invention overcomes these and associated drawbacks of prior art centrifugal pumps by totally eliminating the rotor blades and any bearing mounting associated therewith. Briefly, the present invention contemplates a hermetically sealed circular chamber having an inlet adjacent to the center of the chamber and outlet adjacent the periphery of the chamber. The centrifugal force of the pump is created by one or more roller elements riding in a circular raceway inside the chamber and adjacent to the periphery thereof. The raceway is comprisedof two tracks mounted on the top and bottom of the chamber respectively with a slot therebetween, the slot providing an opening small enough so that the roller elements are precluded from passing therethrough.

Mounted outside the chamber is a device for creating a rotating magnetic field. Since the roller elements are at least partially metallic and the chamber is nonmetallic, the rotating magnetic field causes the roller elements to rotate in the raceway. The roller elements being freely mounted also rotate about their on axis as they pass around the raceway so that a centrifugal force is created into the chamber with minimum frictional resistance between the rollers and the raceway.

Consistent with this brief description, it is a primary object of this invention to provide a centrifugal pump having a freely mounted prime mover located therein.

it is another object of this invention to provide a centrifugal pump of simple construction that avoids all possibilities of leakage from the chamber of the pump.

It is another object of this invention to provide a centrifugal pump that is highly efficient and does not have any rotor blades or a shaft for mounting any prime mover for fluid passed thereinto.

lt is a further object of this invention to provide a centrifugal pump that does not require any sealing structure for the prime mover.

It is yet a further object of this invention to provide a centrifugal pump that is hermetically sealed and wherein the prime mover is freely mounted within the chamber of the pump.

it is a more specific object of this invention to provide a centrifugal pump having a circular chamber with a raceway around the periphery thereof and roller elements freely mounted within the raceway, the roller elements being rotated in the raceway by a rotating magnetic field positioned completely outside the chamber.

Another specific object of this invention is to provide a centrifugal pump of the nature described having a plurality of stages including a plurality of raceways with roller elements positioned therein and driven about the raceways with roller elements positioned therein and driven about the raceways by a rotating magnetic field totally outside the chamber of the pump.

These and other objects of the present invention will become apparent from a detailed description of the preferred embodiment which is illustrative only. This detailed description will be best understood by considering the accompanying drawings wherein:

FIG. 1 represents an elevation, partially in section, of the pump of the preferred embodiment;

FIG. 2 which illustrates a plan section of the pump taken along the line of 2-2 of FIG. 1; and

FIG. 3 which illustrates a modification of the preferred embodiment within the scope of the invention including a centrifugal pump having a plurality of stages.

Referring now to FIG. 1 and 2, therein is shown a centrifugal pump having a circular chamber 1 communicating with the area outside the chamber through an axial inlet conduit 2 and a lateral outlet conduit 3. The circular chamber 1 is constructed of nonmagnetic. material and carries a raceway therein. The raceway is circular and positioned adjacent but away from the periphery of the chamber 1. The raceway is constructed of two circular guide rails or tracks 4 and 5. These tracks are mounted on the bottom and top of the chamber respectively and are separated by a narrow slot. Positioned in terior of the raceway are two metallic balls or roller elements 6 and 7. The roller elements are of a greater diameter than the slot between the two tracks 4 and 5 so that the balls may not pass through the raceway to the outer periphery of the chamber. While these roller elements are shown in spherical shape, any other convenient shape is permissible, e.g., a cylindrical unit, and an elliptical unit, etc.

A ring 8 of highly permeable material is provided outside the chamber 1, coaxial with the inlet 2 and overlying the raceway formed by the tracks 4 and 5. A magnet 9 is placed outside the chamber 1 opposite the ring 8 in such a way that its poles face the ring. The magnet shown is a conventional permanent magnet of U-shape construction and is positioned such that when the magnet is revolved about its axis, the legs of the U" define a circle concentric with the raceway.

The roller elements 6 and 7 are of metallic material and within the field created by the magnet, this field covering the elements and the ring (polar piece).

The magnet 9 may be rotated by any suitable mechanical means about its axis 10. This rotation of the magnet creates a rotating magnetic field which carries the metallic roller elements 6 and 7 in a circular path along the raceway formed by the tracks 4 and 5. Since the roller elements 6 and 7 are freely positioned within the chamber 1, they not only rotate about the path of the raceway but also rotate about their own axis which produces a significantly efficient pump due to the minimized frictional effect. The rotation of the magnet causes the roller elements to be pressed on the circular raceway and start rolling without rubbing-rotating on the axis of the forces produced by the magnetic field.

Fluid introduced into the chamber 1 through the conduit 2 is whirled by the roller elements 6 and 7 in their gyratory course. Due to the centrifugal force thus created, the fluid is forced to the periphery of the chamber through the slot in the raceway where it escapes through conduit 3 due to the centrifugal propulsion on the fluid. As is apparent, the outlet 3 could be positioned tangentially of the circular chamber 1. Further, the inlet 2 does not have to be in the center of the chamber nor perpendicular thereto. it is within the scope of this invention to provide the inlet at an angle to the plane of the chamber 1 to thereby introduce the fluid into the chamber in a swirling motion.

The roller elements 6 and 7 may be coated with a corrosionresistant material and the chamber 1 may be of the same material, provided this material is nonmagnetic. As an example, polytetrafluoroethylene is an excellent material for the pump since it has a high resistance to corrosion and is capable of functioning within a large temperature range.

As is apparent from the foregoing description, the invention presents several advantages over the prior art. One of the primary advantages is that the pump does not require any elements subject to friction other than the very minimal friction of the two surfaces in rolling contact. No bearings or points in contact with mobile elements is required and as a consequence the linear speed of the roller elements can be very high without any mechanical drawback. The pump of the invention is completely free of leaks and no communication is possible between the inside and the outside of the chamber other than through the inlet 2 and outlet 3.

While the embodiment of FIG. 1 illustrates a single magnetic field, more than one field is also possible, with corresponding groups of roller elements. It is thus possible to increase the efficiency of the device. Further, the field can be created by other means than rotating a permanent magnet. It is within the scope of this invention to use rotating electromagnets or a circular group of nonmoving electromagnets energized by a rotating contact, the rotating fields being produced by AC current. As is apparent, should the fluid being pumped through the instant device include magnetic particles, it would be possible to eliminate the roller elements and raceway since the magnetic particles suspended in the fluid would be rotated by the rotating magnetic field and thus cause a centrifugal force to pump the fluid through the outlet 3.

- A further modification within the scope of this invention is shown in FIG. 3 and includes the provision of several concentric raceways in the circular chamber for corresponding groups of roller elements. The roller elements may be driven along the paths of the separate raceways by one or more rotating magnetic field. In this way, a multistage pump is provided, capable of creating high pressures.

As shown in FIG. 3, a circular chamber 11 communicates with the exterior of the chamber by axial conduit 12 and lateral conduit 13. The chamber is constructed of nonmagnetic material, as for instance, synthetic resin. in this chamber are provided three concentric raceways 14, 15 and 16 similar to the raceways constituted by tracks 4 and 5 shown in F IG. 1.

The aggregate comprises four concentric cavities-the circular chamber 11 and three annular cavities illustrated by reference numerals 18, 19 and 20. Cavity or chamber 11 communicates in its center with conduit 12 and peripherally with cavity 18. The cavity 18 communicates at its periphery with cavity 19 which in turn communicates with cavity 20 adjacent the outer periphery of the chamber.

The cavity 20 is connected to the exterior of the pump through the conduit 13. The cavities l1, l8 and I9 contain roller elements 21, 22, 23, 24, and 26. They are carried in the circular path of the raceways by a rotating magnetic field similar to the manner described in conjunction with the embodiment of FIG. 1. Liquid introduced through conduit 12 is whirled about by the gyrating roller elements 23 and 24 in cavity or chamber 11 which propels the fluid into cavity 18. Roller elements 22 and 25 in cavity l8 propel the fluid through their rotating motion to the cavity l9 and so forth until the fluid reaches cavity 20 where it exits through the outlet conduit IS. The propulsion forces are additive from the inlet 12 and chamber II to cavity 20 and constitute pressure stages to enable very high pressures to be created in the chamber adjacent the outlet conduit 13. Operation of this multistage pump permit easy attainment of relatively high pounds per square inch in the centrifugal pump. As the roller elements circulate practically without any friction, relatively soft metals maybe used as the material for the roller elements provided this metal shows a suflicient magnetic permeability. The basic requirement for the metal of the roller elements is that they be resistant to corrosion and this effect may be attained by coating the roller elements with a suitable material.

Polyacrylic resins may be used for the coating material as no significant wear is expected. The raceways may also be coated of this material. It may also be of advantage to construct the chamber of the pump of transparent material reinforced by any suitable means.

Due to the rotation of magnetic fields, Foucault currents can be created during normal operation at the constant speed but they do not disturb the operation of the pump. The practically total absence of frictional forces allow very high gyrating speed of the roller elements so that the pump will operate to propel large volumes of fluid efficiently. However, starting of the pump should be progressive and a rheostat can be used to effect this initial startup.

While the description of the invention has been made using express terms for the sake of clarity, it is to be recognized that the breadth of the invention is limited only by the scope of the appended claims.

What is claimed is:

1. A centrifugal pump including:

a. a substantially circular chamber having an inlet and outlet,

b. at least one raceway positioned in said chamber so as to define an annular portion of said chamber outside said raceway,

c. a prime mover positioned inside said raceway,

d. driving means for said prime mover located completely outside said chamber, and

e. a passage in said raceway communicating the portion of the chamber interior of the raceway with the annular portion of the chamber.

2. A centrifugal pump as defined in claim 1 wherein said prime mover includes at least one freely mounted roller element.

3. A centrifugal pump as defined in claim 2 wherein said roller element is spherical.

4. A centrifugal pump as defined in claim 3 wherein said spherical roller element is metallic with a wear resistant coating.

5. A centrifugal pump as defined in claim 1 wherein said inlet is interior of said raceway.

6. A centrifugal pump as defined in claim 5 wherein said outlet is adjacent the periphery of said chamber.

7. A centrifugal pump as defined in claim 1 wherein there is a single raceway.

8. A centrifugal pump as defined in claim 1 wherein said raceway includes at least one annular track mounted in said chamber.

9. A centrifugal pump as defined in claim 8 wherein there are two coaxial annular tracks, one mounted on the top and the other mounted on the bottom of said chamber.

7 IOTA centrifugal pump as defined in claim 1 wherein said driving means is a rotating magnetic field coaxial with said raceway.

11. A centrifugal pump as defined in claim 10 wherein said rotating magnetic field is a permanent U-shaped magnet and the legs of the magnet face the raceway and the circle generated by rotation of the magnet is coextensive with said raceway.

12. A centrifugal pump as defined in claim 1 wherein said chamber is a hermetically isolated unit and the only communication between the area inside the chamber and the area outside the chamber is through said inlet and said outlet.

13. A centrifugal pump as defined in claim 1 wherein there are a plurality of concentric raceways each having at least one prime mover associated therewith.

14. A centrifugal pump as defined in claim 13 wherein each of said plurality of raceways has at least one circular roller element freely positioned therein.

15. A centrifugal pump as defined in claim 14 wherein said raceways define a plurality of annular cavities within said chamber. 

1. A centrifugal pump including: a. a substantially circular chamber having an inlet and outlet, b. at least one raceway positioned in said chamber so as to define an annular portion of said chamber outside said raceway, c. a prime mover positioned inside said raceway, d. driving means for said prime mover located completely outside said chamber, and e. a passage in said raceway communicating the portion of the chamber interior of the raceway with the annular portion of the chamber.
 2. A centrifugal pump as defined in claim 1 wherein said prime mover includes at least one freely mounted roller element.
 3. A centrifugal pump as defined in claim 2 wherein said roller element is spherical.
 4. A centrifugal pump as defined in claim 3 wherein said spherical roller element is metallic with a wear resistant coating.
 5. A centrifugal pump as defined in claim 1 wherein said inlet is interior of said raceway.
 6. A centrifugal pump as defined in claim 5 wherein said outlet is adjacent the periphery of said chamber.
 7. A centrifugal pump as defined in claim 1 wherein there is a single raceway.
 8. A centrifugal pump as defined in claim 1 wherein said raceway includes at least one annular track mounted in said chamber.
 9. A centrifugal pump as defined in claim 8 wherein there are two coaxial annular tracks, one mounted on the top and the other mounted on the bottom of said chamber.
 10. A centrifugal pump as defined in claim 1 wherein said driving means is a rotating magnetic field coaxial with said raceway.
 11. A centrifugal pump as defined in claim 10 wherein said rotating magnetic field is a permanent U-shaped magnet and the legs of the magnet face the raceway and the circle generated by rotation of the magnet is coextensive with said raceway.
 12. A centrifugal pump as defined in claim 1 wherein said chamber is a hermetically isolated unit and the only communication between the area inside the chamber and the area outside the chamber is through said inlet and said outlet.
 13. A centrifugal pump as defined in claim 1 wherein there are a plurality of concentric raceways each having at least one prime mover associated therewith.
 14. A centrifugal pump as defined in claim 13 wherein each of said plurality of raceways has at least one circular roller element freely positioned therein.
 15. A centrifugal pump as defined in claim 14 wherein said raceways define a plurality of annular cavities within said chamber. 